Hand-operated crimping tool



March 5, 1957 o. D. SCARBOROUGH I 2,783,669

' HAND-OPERATED CRIMPING TOOL Filed June 25, 1954 so s2 5 4 53 50:

v INVENTOR.

O. D. Scmzaogoueu United States Patent HAND-OPERATED CRIMPING TOOL 0.Scarborough, Hastings, Nelm, assignor to the United States of America asrepresented by the Secretary of the Navy Application June 25, 1954,Serial No. 439,496 3 Claims. (Cl. 81-15) (Granted under Title 35, U. S.Code (1952), see. 266) The invention described herein may bemanufactured and used by or for the Government of the United States ofAmerica for governmental purposes without the payment of any royaltiesthereon or therefor.

This invention relates to crimping tools and more particularly to ahand-operated crimping tool for indenting the sides of a sleeve or tubeover an elongated concentric member to secure the sleeve or tube and theconcentric member together against longitudinal separatron.

A number of crimping tools are known which are used for crimping theferrules of electrical terminals to electrical conductors without thenecessity of making solder joints. In most of these crimping tools thejaws of the crimping head are limited in their compressive'directiononly by their actual engagement whereby the ferrule of the electricalterminal can be compressed to the extent of the power applied to thehandles. Consequently sharp jaws are avoided to prevent a cutting actionof the jaws in the ferrule. Where such crimping tools are used merely tosecure a flexible tube over an electrical conductor, and particularlywhere the tube is plastic, great care must be exercised to preventsevering the'tube.

In the present invention a crimping tool having plierslike handles has ameans thereon to limit the approach of the jaws at a predeterminedposition. The'jaws are detachable and each has staggered projectionsthereon directed toward the companion jaw with the projections of eachjaw also staggered with respect to the projections of the companion jaw.The top plane of all the projections of one jaw passes through the topplane of all the projections of the other jaw such that a tube encasedconcentric member compressed between the jaws will have a plurality ofdeformed indentations therein securing the tube to the concentric memberagainst longitudinal separation. This tool is particularly useful incrimping plastic sleeves or tubes over bare or insulated electricalconductors, or in crimping metal sleeves over insulated conductors. Itis therefore a general object of this invention to provide ahand-operated crimping tool for indenting sleeve or tubular members overinner enclosed members to secure them against longitudinal separation.

These and other objects, advantages, features, and uses will be moreapparent as the description proceeds when considered with theaccompanying drawing, in which;

Fig. l is a side elevational view of the crimping tool of thisinvention;

Figs. 2, 3, and 4 are top, side, and end elevational views,respectively, of a three-tooth replaceable jaw for the crimping tool;

Figs. 5, 6, and 7 are top, side, and end elevational views,respectively, of a four-tooth replaceable jaw for the crimping tool;

Fig. 8 is an elevational view of the threetooth companion jaws showncrimping a tubular sleeve on an electrical conductor; and

Fig. 9 is a view of a short section of an electrical conductor showing atubular sleeve crimped thereon.

Referring more particularly to Fig. 1, there is shown a crimping tool ofthe hand-operated pliers type having a pair of handles 10 and 11 pivotedat 12 by a rivet, or the like. pivotal movement in both directions by aflat stop bar member 13 pivoted to the handle 11 at 14 by a rivet, orthe like. 15 therein on the end opposite the pivot 14 through which slotis slidably passed a rivet 16, or the like, fixed to the handle 10. Thepositions of the rivets 14 and 16 are each substantially equal indistance from the handle pivot 12. The handles. 10 and 11 are limited inpivotal movement by the limit of the rivet 16 in the slot 15. The barmember 13 may have the elongated slot 15 con: stricted at 17, wheredesirable, to cause the rivet 16 to frictionally pass through theconstriction for the purpose of yieldably holding the tool in thecrimped condition, as will later becomeclearer. The handles may be, andpreferably are, biased outwardly by a spring 18.

Each handle has a short extension forward of the pivotal point 12 topivot a short lever thereon, the handle 10 pivotally connecting a lever20 at 21 by a rivet, or

the like, and the handle 11 pivotally connecting a lever 22 at 23. Thelevers 20 and 22 are each pivotally coupled at 24 and 25, respectively,by rivets, or the like, to a pair of plates 26 to produce a forcemultiplying linkage between the handles 10 and 11 to the forward jawends of the levers 20 and 22, represented by reference characters 27 and28. Where desirable, the levers 20 and 22 may be produced in two partsand selectively coupled by riveting in the slightly displaced ports 29to throw the jaw ends in or out as is well recognized in the art andillustrated in the tool construction in the patent to R. C. Swengel,issued on November 26, 1946, and bearing the PatentNo. 2,411,838. As maybe well un derstood from the above description, movement of the handles10 and 11 toward one another will cause movement of the jaw ends 27 and28 to approach one another. 7

The jaw ends 27 and 28 have a pair of replaceable jaw members 30 thereoneach secured by a cap screw 32. The structure of the jaws is moreparticularly shown in Figs. 2 to 7, inclusive, Figs. 2, 3, and 4 showinga three-tooth crimping jaw and Figs. 5, 6, and 7 showing a four-toothcrimping jaw. Using jaw member 30 as an example in Figs. 2, 3, and 4,the body of the jaw 30 is U-shaped at 35 and has an opening 36 throughone leg thereof for passage of the attaching cap screw 32. The jaw ends27 and 28 of the tool fit within the U-shape recess or opening 35 ofeach jaw member 30. The base portion of the jaw member 30 has a fiatface 37 with three projecting teeth 38, 39, and 40 thereon. Teeth 38 and40 are in line along one edge of the jaw 30 and near respective oppositeends. Tooth 39 is positioned along the opposite edge of the jaw 30 andcentrally thereof to provide a staggered arrangement of the teeth. Theteeth are all of the same extent and are illustrated herein as havingsubstantially sharp corners which is preferable but not necessary. Asseen in Fig. 3, the extent of the teeth inwardly toward the center ofthe face 37 is short of the center leaving a central path through theteeth of predetermined width dependent on the tube size to be crimped.The jaw members 30 are used in pairs, the arrangement of the jaw memberswith the base face portions 37 facing each other, as they are supportedin the tool, bringing the tooth 39 of one block between the teeth 38 and40 of the companion block. The teeth of one jaw are thus complementallyspaced with respect The handles 10 and 11 are limited in their The barmember 13 has an elongated slot jaw member 30' which is attachable toeach of the jaw ends 2'7 and 28 in the same manner as the jaw member 30.The jaw member 30 is provided with four teeth on the base portionthereof arranged in staggered relationship to each other in such mannerthat the teeth of one jaw, like the jaw members 30, are complementallyspaced with respect to the teeth of the other jaw when assembled in thetool although any desirable number of teeth may be used to meet certaincrimping requirements.

In Fig. 8 an electrical conductor 50 isshown having a plastic tube 51crimped thereon with the jaw members 30, for example, forced to theirextreme crimpingconditions. The conductor and tube are positioned inbe-- tween the jaw members 30 along the path between the teeth such thatin the crimped condition the teeth indent the'wall of the tube into theconductor. The tool will yieldably hold in the crimped condition, whennecessary, by the friction means 16, 17. When the crimpis released thetube indentations remain in thetube and conductor which unite theconductor and tube against longitudinal separation. While there may be apartial retur'nof the indented portions, the indentations are madesufficiently deep to unite the conductor and tube in the settled state.The conductor and tube combination is shown in Fig. 9 after beingremoved from the crimping tool, looking downwardly. The teeth 38 and 40made the indentations 52 and 53, respectively, and the tooth 39'made theindentation 514.

In the operation of the crimping tool iti-s only necessary to place theopen jaw members 30, for example, over a tube to be crimped with thehandles 10 and 11 extending laterally therefrom. The handles are broughttogether to their limit which closes the jaw members over the tube tothe position shown in Fig. 8. The force on the handles is released andthe tool removed. This crimping exercise can be carried out at differentplaces along the tube, as desired. Jaw members of four or more teeth maybe used in the tool to increase the number of indentations made. Sincethe jaw members are.

limited in their approach, the tube is indented only and other to apredetermined approach limit, each jaw having a plurality of teethextending outwardly therefrom in'the direction of the companion jaw withthe teeth lying in each of two rows across: the jaw with the edges ofthe teeth along one row adjacent the edges along the other row beingseparated a predetermined amount providing a path in which elongatedconcentric members to be crimped may partia'lly'lie, said teeth of onejaw being complementally spaced with respect to the teeth of thecompanion jaw so that said jaws when forced to their approach limit willhave the end plane of the teeth of one jaw pass the end plane of theteeth of the companion jaw with the teeth of one jaw in spatial relationwith respect to the teeth of the companion jaw whereby chordwiseindentations may be impressed in the walls of concentric members. i i V2. A crimping tool as set forth in claim 1 wherein each of said teethare of square configuration whereby in the crimping operation aplurality of V-shaped indentations are impressed chordwise in the,concentric members. v

.3. A crimping 'tool for securing elongated concentric members againstlongitudinal separation comprising, a

-. pair of pivoted handles each having a jaw supporting portionthereon,a detachable jaw on each jaw supporting portiomeach detachable jawhaving a plurality of rows of upstanding teeth thereon arranged toextend into the area between the teeth of the companion jaw in lateralspatial relation, said rows of teeth on each jaw being arranged instaggered relationship to each other and providing an open paththerebetween with the teeth of one jaw being complementally spaced withrespect to the teeth of the other jaw so that the teeth of one jaw willbe extendable into the areas'between the teeth of the companion jaw withthe rows of teeth in alignment whereby elongated concentric memberslying partially in said open path compressed between said detachablejaws by said pivoted handles will be indented by chordwise depressionsarranged in staggered relationship to each other in the walls thereof.

References Cited in the file of this patent UNITED STATES PATENTS

